An artist's concept depicts a thick "doughnut" of dust encircling a quasar, which is a smaller disk of super-hot gas encircling a supermassive black hole. Astronomers recently discovered that a disk like this one contains enough water to fill Earth's oceans 140 trillion times over. The disk encircles a quasar that is billions of light-years away. Its central black hole is billions of times more massive than the Sun, and its surrounding disk produces millions of times more energy than all of the stars in our entire Milky Way galaxy. [NASA/ESA]

The stars are chemical factories — they forge new elements in the nuclear furnaces at their cores. A good example is Antares, the bright heart of Scorpius, which is low in the southwest at nightfall.

Antares is so massive that it will forge carbon, oxygen, silicon, iron, and more. At the end of its life it’ll explode, creating even more elements. The blast will spread the atoms it created far and wide.

Once the elements are out in space, though, the chemistry is far from over. In fact, the space between stars is also a chemical factory, in the form of giant clouds of gas and dust. The elements within these clouds combine to make molecules.

Astronomers recently discovered molecules of hydrogen peroxide in a cloud that surrounds the star Rho Ophiuchi, which stands a little above Antares. Hydrogen peroxide consists of two atoms of hydrogen and two atoms of oxygen — the same elements that make up water.

And in the far reaches of the universe — about 12 billion light-years away — another team found water itself — more than a hundred million million times more water than in all of Earth’s oceans. The water surrounds a supermassive black hole that could be one of the biggest ever discovered.

The water and hydrogen peroxide show that many of the basic building blocks of life are common throughout our galaxy and beyond — all created in the chemical factories of the stars.